Traditionally, an ophthalmic device, such as a contact lens, an intraocular lens, or a punctal plug, included a biocompatible device with a corrective, cosmetic, or therapeutic quality. A contact lens, for example, may provide one or more of vision correcting functionality, cosmetic enhancement, and therapeutic effects. Each function is provided by a physical characteristic of the lens. A design incorporating a refractive quality into a lens may provide a vision corrective function. A pigment incorporated into the lens may provide a cosmetic enhancement. An active agent incorporated into a lens may provide a therapeutic functionality. Such physical characteristics are accomplished without the lens entering into an energized state. An ophthalmic device has traditionally been a passive device.
Novel ophthalmic devices based on energized ophthalmic inserts have recently been described. These devices may use the energization function to power active optical components. For example, a wearable lens may incorporate a lens assembly having an electronically adjustable focus to augment or enhance performance of the eye, and/or embeddable microelectronic devices that can be useful for the diagnosis and treatment of various health conditions or diseases.
Retinal vascular imaging has recently been explored as a non-invasive alternative tool to analyze the role and pathophysiology of the microvasculature. For instance, research has demonstrated that a correlation exists between conditions of the retinal vascularization, forming part of the microvasculature, and cardiovascular disease and hypertension. Typically, screening for the diagnosis and monitoring of cardiac conditions is done by an electrocardiogram (also known as an ECG or EKG). An electrocardiogram can be used to measure the rate and regularity of heartbeats, the size and position of the chambers, the presence of any damage to the heart, and the effects of drugs or devices used to regulate the heart by analysis of the electrical activity of the heart over a period of time, as detected by electrodes attached to the surface of the skin and recorded by a device external to the body. However, getting an electrocardiogram for many patients can not only be highly burdensome but is also not recommended for individuals absent additional symptoms or for patients who are at low risk. Moreover, for those at higher risk electrocardiogram screening results can be inconclusive.
The microvasculature includes vessels between 100 μm and 300 μm making the study and analysis of these vessels difficult in part due to their size. In addition, until recently the methods and procedures used to investigate the microvasculature have all been invasive and require highly specialized tools and settings. More recently however, with advances in photographic image techniques and computer-assisted image analysis techniques, alternative techniques that utilize non-invasive large complex cameras have been explored. These non-invasive techniques in turn can allow physicians and researchers to image and study the retinal vascularization of a patient.
Although these new non-invasive techniques can be useful for the study and understanding of microvascular changes, they continue to require specialized equipment and settings for the imaging of the retinal vascularization of a patient. Consequently, the timing and changes that can be observed are interrupted by large periods of time (i.e. time between appointments), and therefore less than optimal. In order to overcome the aforementioned limitations and improve the accuracy of the retinal vascularization analysis, novel and reliable systems/methods that can monitor changes in the retinal vascularization of a patient innocuously and without significant delay are desired.